I'm aware of FATCA. It's my understanding SEC uses SWIFT as leverage over foreign banks, and threatens to restrict usage if not compliant.

Cryptocurrencies obviate the established monetary transfer system. Not to mention exchanges don't have to deal with banks to begin with. The only exchanges I could see getting targeted are those exchanging fiat currency to crypto.

Also, how could any government even think of moving on decentralized exchanges? Target the coders?